CCNA Security Chapter 7 Exam v2

CCNA Security Chapter 7 Exam Answer v2

  1. What is the focus of cryptanalysis?

    • hiding secret codes
    • developing secret codes
    • breaking encrypted codes
    • implementing encrypted codes
  2. How many bits does the Data Encryption Standard (DES) use for data encryption?

    • 40 bits
    • 56 bits
    • 64 bits
    • 72 bits
  3. Which statement describes the Software-Optimized Encryption Algorithm (SEAL)?

    • SEAL is a stream cipher.
    • It uses a 112-bit encryption key.
    • It is an example of an asymmetric algorithm.
    • It requires more CPU resources than software-based AES does.
  4.  

  5. Which encryption algorithm is an asymmetric algorithm?

    • DH
    • SEAL
    • 3DES
    • AES
  6. An online retailer needs a service to support the nonrepudiation of the transaction. Which component is used for this service?

    • the private key of the retailer
    • the unique shared secret known only by the retailer and the customer
    • the public key of the retailer
    • the digital signatures
  7. In which situation is an asymmetric key algorithm used?

    • Two Cisco routers authenticate each other with CHAP.
    • User data is transmitted across the network after a VPN is established.
    • An office manager encrypts confidential files before saving them to a removable device.
    • A network administrator connects to a Cisco router with SSH.
  8. What is the purpose of a nonrepudiation service in secure communications?

    • to ensure that encrypted secure communications cannot be decoded
    • to confirm the identity of the recipient of the communications
    • to provide the highest encryption level possible
    • to ensure that the source of the communications is confirmed
  9.  

  10. Which objective of secure communications is achieved by encrypting data?

    • integrity
    • authentication
    • confidentiality
    • availability
  11. Why is the 3DES algorithm often preferred over the AES algorithm?

    • 3DES is more trusted because it has been proven secure for a longer period than AES.
    • AES is more expensive to implement than 3DES.
    • 3DES performs better in high-throughput, low-latency environments than AES.
    • Major networking equipment vendors such as Cisco have not yet adopted AES.
  12. What is the most common use of the Diffie-Helman algorithm in communications security?

    • to create password hashes for secure authentication
    • to provide routing protocol authentication between routers
    • to encrypt data for secure e-commerce communications
    • to secure the exchange of keys used to encrypt data
  13. Which type of encryption algorithm uses public and private keys to provide authentication, integrity, and confidentiality?

    • symmetric
    • shared secret
    • IPsec
    • asymmetric
  14.  

  15. How do modern cryptographers defend against brute-force attacks?

    • Use statistical analysis to eliminate the most common encryption keys.
    • Use a keyspace large enough that it takes too much money and too much time to conduct a successful attack.
    • Use an algorithm that requires the attacker to have both ciphertext and plaintext to conduct a successful attack.
    • Use frequency analysis to ensure that the most popular letters used in the language are not used in the cipher message.
  16. Which encryption protocol provides network layer confidentiality?

    • IPsec protocol suite
    • Transport Layer Security
    • Secure Hash Algorithm 1
    • Secure Sockets Layer
    • Keyed MD5
    • Message Digest 5
  17. Refer to the exhibit. Which encryption algorithm is described in the exhibit?

    CCNA Security Chapter 7 Exam Answer v2 001

    CCNA Security Chapter 7 Exam Answer v2 001

    • RC4
    • AES
    • 3DES
    • DES
    • SEAL
  18.  

  19. Which statement describes asymmetric encryption algorithms?

    • They have key lengths ranging from 80 to 256 bits.
    • They include DES, 3DES, and AES.
    • They are also called shared-secret key algorithms.
    • They are relatively slow because they are based on difficult computational algorithms.
  20. Which two non-secret numbers are initially agreed upon when the Diffie-Hellman algorithm is used? (Choose two.)

    • binomial coefficient
    • generator
    • elliptic curve invariant
    • prime modulus
    • topological index
    • pseudorandom nome
  21. In what situation would an asymmetric algorithm most likely be used?

    • logging onto a computer
    • making an online purchase
    • uploading a networking book chapter using FTP
    • transferring a large stream of data between two corporate locations
  22. Why is asymmetric algorithm key management simpler than symmetric algorithm key management?

    • It uses fewer bits.
    • Only one key is used.
    • Two public keys are used for the key exchange.
    • One of the keys can be made public.
  23. What is the purpose of code signing?

    • source identity secrecy
    • integrity of source .EXE files
    • reliable transfer of data
    • data encryption
  24.  

  25. Which algorithm can ensure data confidentiality?

    • MD5
    • PKI
    • RSA
    • AES
  26. What is the purpose of a digital certificate?

    • It guarantees that a website has not been hacked.
    • It authenticates a website and establishes a secure connection to exchange confidential data.
    • It provides proof that data has a traditional signature attached.
    • It ensures that the person who is gaining access to a network device is authorized.
  27. Fill in the blank.

    A shared secret is a key used in a   symmetric  encryption algorithm.